Bitter cold could follow upcoming warm spell

Temperatures are expected to be on the rise this week, with daytime highs topping 40 by Wednesday and possibly reaching 50 by this weekend.

But, don’t put your winter parka too far away.

Alex Sosnowski, expert senior meteorologist with AccuWeather.com, reports on a possible change in weather patterns beginning near or just past the middle of January.

Although much of the U.S. has been reporting higher-than-average temperatures so far this winter, Sosnowski notes that a phenomenon known as sudden stratospheric warming has occurred in the arctic region during the past few days. The stratosphere is located between 6 miles and 30 miles above the ground.

Often when this occurs, it forces cold air to build in the lowest layer of the atmosphere then to drive southward.

Accuweather.com expects to see cold air spreading out from central Canada by the third week of January.

“Initially, the cold may seem to be run-of-the-mill or even delayed, but once the cold air engine starts, it may run for quite a while with progressively colder and colder waves of air,” said AccuWeather.com Expert Senior Meteorologist Brett Anderson.